The Standard Model of particle physics is a theory of three of the four known fundamental interactions and the elementary particles that take part in these interactions. These particles make up all visible matter in the universe.
Every high energy physics experiment carried out since the mid-20th century has eventually yielded findings consistent with the Standard Model.
Still, the Standard Model falls short of being a complete theory of fundamental interactions because it does not include gravitation, dark matter, or dark energy. It is not quite a complete description of leptons either, because it does not describe nonzero neutrino masses, although simple natural extensions do.
Gluons mediate the Strong Force. They have no mass, no electric charge and no weak charge. So depicting gluons visually is a real challenge. To begin with, there are eight of them, and each carries a combination of color charge. Secondly, there are no free gluons, they exist only virtually when two quarks interact.
Third, since the gluons have their own color charge, they generate secondary virtual gluons, and these generate other gluons, ad infinitum. This means there is such an ongoing storm of these gluons that the whole process is impossibly complicated.
But undaunted, we press on. We know that when gluons cause two quarks to interact, the quarks swap color, and since color is conserved, the gluon must have at least two colors of its own.
Next, we know that the strong force mediated by the gluons increases in strength, as the quarks get farther apart. This means the gluon field is what is called a flux tube and leads to a gluon shaped like a string.
The Cassiopeia Project - making science simple!
The Cassiopeia Project is an effort to make high quality science videos available to everyone. If you can visualize it, then understanding is not far behind.